High Frequency Active Auroral Research Program, jointly funded by the US Air Force, the US Navy, the University of Alaska and the Defence Advanced Research Projects Agency (DARPA).
The HAARP complex is situated in Gakona, Alaska. It's a 23-acre lot containing 180 towers, 72 feet in height, forming a "high-power, high frequency phased array radio transmitter" capable of beaming in the 2.5-10 megahertz frequency range, at more than 3 gigawatts of power (3 billion watts).
The Pentagon's provocative plan to superheat the earth's ionosphere using HAARP's phased-array transmitters. In effect, to zap the earth's ionosphere with high-frequency radio waves. Why irradiate the charged particles of the ionosphere which when energised by natural processes make up the lovely and famous phenomenon known as the Northern Lights?
Co-sponsors of the programs claim "Its purpose is to analyse the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance purposes (such as missile detection)".
The Internet abounds with theories concerning the real reasons for HAARP. However, an assortment of more grounded critics--environmentalists, Native Americans and Alaskan citizens among them--argue that the military does indeed have Strangelovian plans for this unusual hardware, applications ranging from "Star Wars" missile defence schemes to weather modification plots and perhaps even mind control experiments.
HAARP technology is rightly or wrongly assumed to be descended from the works of Nikola Tesla credited as being the inventor of wireless technology.